STRUCTURAL AND METAMORPHIC EVOLUTION OF PERMIAN MIGMATITES IN KALASU AREA, NORTH WESTERN CHINA
The CAOB represent a huge accretionary system which has evolve from Neoproterozoic to Triassic. We are studying a Permian migmatitic zone in Chinese Altai, North Western China. This migmatitic zone is composed of cordierite, sillimanite and garnet and represent a High T/ Low P metamorphism. Our structural investigation has shown that prior to the Permian migmatization there was a sub horizontal S1 fabric. The migmatite where possibly emplaced during a strong event with occurrence of upright to isoclinal F2 folds. The existence of Permian F2 folds in Chinese Altai questioned us about the tectonic settings in Western CAOB. Could these HT migmatite shed light on the final collision between the Junggar domain and the Chinese Altai or is it a link to the Tarim mantle Plume as suggested by some authors. During this Ph.D we will focus on pseudosection modelling as well as monazite dating in order to answer this question.